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1.
Ingestion of placenta and amniotic fluid has been shown to enhance opioid-mediated analgesia in rats produced by morphine injection, footshock, vaginal/cervical stimulation, and during late pregnancy. The present study was designed to investigate the effects of amniotic fluid ingestion on the characteristics of morphine dependency and withdrawal. Tail-flick latencies in Long-Evans rats were determined before and after repeated daily injections of morphine sulfate. It was found that ingestion of amniotic fluid after establishment of the morphine dependency, coupled with an injection of an otherwise ineffective dose of morphine, enhanced analgesia in morphine-dependent rats, and reversed hyperalgesia seen during withdrawal from morphine dependency.  相似文献   
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Over the past two decades, the role of radiolabeled monoclonal antibodies has been steadily growing in clinical practice, particularly for staging and locating a variety of neoplasms. This is due largely to the availability of these products in pharmaceutical quantities as well as the relatively low incidence of adverse reactions following the intravenous administration of antibodies to patients. One particular area of oncology where radiolabeled monoclonal antibodies are most likely to play an extremely important clinical role is in the evaluation of patients with colon and rectal carcinomas. In this report, we review the current utilization of tumor-associated monoclonal antibodies in the preoperative as well as postoperative screening of patients with colorectal carcinoma.  相似文献   
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The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
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Parental and professional responses to questionnaires evaluating a paediatric disability service are reported and the viability of auditing structural, process, and outcome aspects of clinical practice are discussed. Expectations of waiting time to first appointment (met for only 52% of consumers) illustrate structural issues. Process issues are reflected in consumer reactions to outreach work (for example, 94% of parents and 84% of professionals found this supportive). Outcome measures such as consumer satisfaction with the service (76% of consumers reported being 'very satisfied' and 20% 'fairly satisfied') suggest that service aims are being met. Good concurrence of service aims with consumer needs is indicated by parental reasons for referral (for example, 75% for diagnostic help, 73% for a better understanding of the disorder, 88% for practical help), referrers' reasons (for example, 55% for a second diagnostic opinion, 45% due to lack of local expertise), and reports from most other professionals involved with the case that a similar service was not provided locally.  相似文献   
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We have found that neoplastic transformation alters the ability of cells to grow on substrata of tissue extracts, "biomatrices", enriched in extracellular matrix. Tumor cells were able to survive and grow at lower densities and on more types of biomatrices than normal cells. When plated at high densities (greater than 10(5) cells/60 mm dish), tumor cells attached with equal efficiency and grew at similar rates and to equivalent saturation densities on biomatrices derived from all tissues. However, at low (10(2)-10(4)/60-mm dish) seeding densities, the tumor cells grew only on certain types of biomatrix. For the various hepatoma and mammary carcinoma cell lines tested, the tissue specificity in clonal growth on biomatrices correlated with their organ site specificity for metastasis in vivo in immunosuppressed, athymic nude mice. Analysis of the effects of purified matrix components (adhesion proteins, collagens, glycosaminoglycans) indicated that only the glycosaminoglycans influenced density-dependent survival and growth of tumor cells with effects that differed with respect to the cell's metastatic potential. The results indicate that the ability of tumor cells to colonize specific tissues represents, in part, regulation of low density survival and growth by extracellular matrix and are suggestive that one of the matrix components responsible may be proteoglycans or their glycosaminoglycan chains.  相似文献   
7.
Natural killer (NK) cell activity was assessed in the peripheral blood of 20 patients with growth hormone (GH) deficiency due to a hypothalamic deficit of GH-releasing hormone (GHRH). All patients failed to respond to at least two provocative tests of GH secretion (GH below 7 ng/ml) but responded to a single GHRH iv bolus injection (1 microgram/kg body wt). In 14 of the 20 patients (20 determinations), lymphocyte subsets were also measured; in all patients the distribution of lymphocyte subsets was within the normal range. More importantly, NK cell activity in the 20 patients was significantly lower than in controls (P less than 0.01). To assess the in vivo effect of GH and GHRH on NK activity and lymphocyte subset distribution, immunologic tests were performed (i) before and after a single iv bolus injection of GHRH (1 microgram/kg body wt) in six patients; (ii) before and after 3 weeks of GHRH treatment (3-9 micrograms/kg body wt, one to four times daily) in five patients; and (iii) after 6 weeks of GH treatment (5 IU sc every alternate day) in one patient. Neither NK activity nor the distribution of lymphocyte subsets was altered during short-term GHRH administration. In conclusion, low NK activity is found in GH-deficient patients, and short-term administration of GH or GHRH fails to restore this immunological abnormality. This result suggests that the hypothalamus may be a regulator of NK activity in the human and that patients with hypothalamic deficiencies should be monitored for the development of discrete immunodeficiencies.  相似文献   
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